In general, an illumination device uses a high-pressure mercury lamp, a fluorescent lamp or a sodium lamp as a light source for generating light.
In recent, as light emitting diode (hereinafter, briefly referred to as “LED”) is developed which has a low power consumption and emits light with a high luminance, the illumination device using the LED as a light source is developed and use of the illumination device is gradually increased.
The illumination device using the LED is generally used for replacing the fluorescent lamp. However, the illumination using the LED is recently used for embellishing wall of a building and also decorating the interior of the building. In particular, users who highly regard their individuality mount the illumination device using the LED on a door of car or a body of motorcycle used by the users.
Namely, the illumination device mounted on the fluorescent lamp, car or motorcycle etc. can be produced by using the LED as described above. In particular, a base substrate on which the LED is mounted is formed as an elongated bar so that the users could freely deform the form of the illumination device. A device of such a form is referred to as an LED bar.
The users can construct the illumination device reflecting their own individuality by cutting the LED bars to a size desired by the users and combining the cut LED bars into a form desired by the users.
Namely, the users who want to use the LED bar for replacing the fluorescent lamp may use the LED bar as a light source for LED fluorescent lamp by cutting the LED bar to a length corresponding to the length of tube constituting the fluorescent lamp and then mounting it on the tube.
Furthermore, the users who want to use the LED bar for various decorations may use the LED bar by cutting the LED bar to the length of device on which the LED bar is to be mounted.
FIG. 1 is a circuit diagram of a conventional LED bar, FIG. 2 is an example view for describing a state of use of the conventional LED bar, FIG. 3 is an external configuration view of an embodiment of the conventional LED bar, and FIG. 4 is an external configuration view of an LED unit cut from the conventional LED bar illustrated in FIG. 3 to be used.
The conventional LED bar (10) has three LEDs (LED1, LED2, LED3) (11) and a single resistor (12) which are connected in series on a base substrate (14), as illustrated in FIGS. 1 and 3, with links (13) as a boundary.
The conventional LED bar (10) may be applied to an illumination device, in the form as illustrated in FIGS. 1 and 3, but also may be applied to the illumination device in the form of LED part cut from the LED bar.
The LED part may be constituted by a single LED unit (10a) as illustrated in FIGS. 2 and 4, but also may be constituted by two or more LED units (10a).
Namely, the link (13) formed in the LED bar (10) are cut so as to obtain a length desired by a user, and thereafter the LED part cut from the LED bar (10) may be used by being mounted on various illumination devices.
Meanwhile, three LEDs (11) and a single resistor (12) are mounted on the LED unit (10a) which is a minimum unit of the LED bar (10 that may be mounted on the illumination device to be used by the user.
Problems of the conventional LED bar as described above are as follows.
Firstly, the conventional LED bar or LED unit has a high power consumption.
In general, the LED has a base value of 3 V to 4.5 V as illustrated in FIG. 2. Therefore, in the case where three LEDs (11) are used while being connected in series as is the case with the conventional LED unit (10a), voltage and current applied to the LEDs have to be increased. Therefore, the conventional LED unit (10a) consumes much power of 12 V to 40 V.
Namely, since the conventional LED unit (10a) has the three LEDs (11) connected with the resistor (12), voltage value of the entire LEDs increases and thus the LED unit has to be configured to be suitable for the voltage of 12 V or more.
Secondly, since the three resistors are formed in the LED unit (10a) which is a minimum unit constituting the conventional LED bar, the user cannot construct the illumination device by variously choosing the number of the LEDs.
Namely, since the three LEDs (11) are mounted on the LED unit (10a) which is the minimum unit that can be used by being mounted on the illumination device, the conventional LED bar may not be used by a user who wants to construct the illumination device by using only one or two LEDs or a user who wants to construct the illumination device by further using one or two LEDs together with LEDs mounted on the at least one LED unit.